Question: what part of the brain lets you move

Darren Rhodes answered on 4 Nov 2016:

Hi there! Thank you for the question.

So, this is not as easy a question as it might seem. So, in your brain, there used to be a really classic view that different parts of the brain does different things. For example, the visual cortex just processed vision (which if you feel the back of your head just by your neck there should be a little bump – this is where you first process things from your eyes). There is an area just below your right ear that is thought to just deal with faces. There is an area above your left ear that deals with understanding words etc. etc.

Ok, so let’s consider the stages of making a movement – such as kicking a ball. First of all, there needs to be an idea to kick the ball, second, there needs to be a plan of how to kick the ball, and third, there needs to be somewhere that sends signals to the muscles to go ahead and kick it. When we decide to do things, this generally engages the frontal lobes. The frontal lobes (just above your eyes), make decisions, feel emotion, and guide your everyday lives – they are what make you human. A signal is then passed from the frontal lobes through some midbrain structures to the planning stage – there is done in a part of the brain called the ‘supplementary motor area’ – which is right at the top of your head, right in the middle. The plans are then passed onto the ‘primary motor cortex’ which sends signals via your spine to your muscles to initiate a movement such as a kick.

Ok, so let me tell you something that is quite a surprising new research finding. I mentioned previously that the first thing needed to initiate a movement is an ‘idea’: so you decide to kick the ball right? However, there is research that argues that actually there are areas of the brain activated around 500 milliseconds before you decide to kick a ball… This means that (possibly) what we think are our own movements based on free-will, are actually decided by the brain before we are aware. Scary!

However, an alternative, modern, radical view to information-processing in the brain – is that whilst some areas do process things separately such as movement, vision, smell, touch, taste and sound – actually, it’s the interaction between different areas of the brain that allows you to process information, and perceive the world. So to try to be clear, there is not one brain region doing one thing – it’s the interaction between all brain regions that contribute to doing something.

I hope this answers your question, and let’s you ask more!

thanks!